Am Samstag, 25. Januar 2014, 15:33:08 schrieb Imran Geriskovan: > Every write on a SSD block reduces its data retension capability. > > No concrete figures but it is assumed to be > - 10 years for new devices > - 1 year at rated usage. (There are much lower figures around)
Where do you have these figures from? For the Intel SSD 320 in this ThinkPad T520 I read about a minimal usable live of 5 years with 20 GB host writes each day in the tech specs. Thats 7300 GB a year or 7,3 TB. I assume metric system here. According to smartctl it has written 241 Host_Writes_32MiB 0x0032 100 100 000 Old_age Always - 360158 360158 * 32 MiB (hmmm, now according to smartctl output this is MiB) which gives almost 11 TiB (10,99). The SSD is over 2,5 years old. Thats less than 5 TiB a year. So that would lay within the range you say. Although the Intel SSD 320 isn´t basically a new device in my eyes. Thats with KDE session with Akonadi and desktop search, sometimes even two KDE sessions and a load of applications running at times. Anyway that SSDs still thinks it is well *new*: 233 Media_Wearout_Indicator 0x0032 100 100 000 Old_age Always - 0 Thats the same media wearout indicator (which takes into account the amount of Erase cycles according to Intel docs) it had at the first day I used it. So I am basically not concerned. While autodefrag mal cause additional writes… that would not even be the main reason for me not to use it at the moment. I am just not convinced that it gives any noticable benefit. And given that… of course it doesn´t make sense to me to have it cause additional writes to the SSD. But I am not using it due to avoiding those additional writes in the first place. My most important recommendation regarding SSDs still is: Keep some space free. Yeah, SSD manufacturers are doing this. But in another Intel SSD PDF I saw some graphs that convinced me in an instant that leaving free about 20% is a good idea. But heck, due to the current fill status of this SSD I do not even adhere to my own recommendation at the moment. Then a occasional fstrim, maybe mount with noatime (cause who cares about it at all?)… Ciao, -- Martin 'Helios' Steigerwald - http://www.Lichtvoll.de GPG: 03B0 0D6C 0040 0710 4AFA B82F 991B EAAC A599 84C7 -- To unsubscribe from this list: send the line "unsubscribe linux-btrfs" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
